3.70 gears and 1/4 mile runs

[E.T.]

Originally Posted by Higgs Boson

you want to cross the finish line at 6500 in fourth.

do you have an auto or stick?

manual trans with 3.91 will go 138 MPH at the top of 4th (6500)....

auto trans with 3.70 will go 132 MPH at the top of 4th (6500)....

of course, that is IF you have the power to push those MPH in the quarter. if you are going 109 in the quarter mile, then you are shifting to fourth right at 99 MPH...and crossing the finish line at 5400 RPMs.

Do us all a favor and look at your RPMs when you cross the finish line next time and you can know for sure. If this is the case, you can use even more gear. A 4.10 will cross at 119 in fourth.

btw, an auto with 3.27s will cross in third at 112 mph....probably result in a faster time.

with that said, if you want the most out of the 1/4 with stock type power and have an auto, get 4.10s. if you want up to 500 rwhp, get 3.70s. stock or bolt on power levels aren't going to push 3.70s, they will be more fun on the street though.

don't fear the gear! my race car has 5.83s....contemplating a move to 6.0s....

Yes, it's an auto. From what you say, it sounds like I'm crossing just after shifting to 4th. I remember glancing down when it did its last shift, and I do believe I was around 99 mph, like you said.

I was just wondering why I was trapping a few mph less than cars with similar mods. From what you said, it sounds like it'd trap higher with the 3.27s, but I'm not going back to those dogs, LOL

Originally Posted by JLE58

What's killing you 1/4 mile time is that 60ft.

I was happy I finally got under 2, but yeah, I bet I could do better and end up with a better ET. It seems like my car is running as it should, I just need to work on the "driver mod."

[inferno camaro]

I thought the same thing about the auto, but you have to figure some converter slip to get an accurate mph.

Originally Posted by Higgs Boson

you want to cross the finish line at 6500 in fourth.

do you have an auto or stick?

manual trans with 3.91 will go 138 MPH at the top of 4th (6500)....

auto trans with 3.70 will go 132 MPH at the top of 4th (6500)....

of course, that is IF you have the power to push those MPH in the quarter. if you are going 109 in the quarter mile, then you are shifting to fourth right at 99 MPH...and crossing the finish line at 5400 RPMs.

Do us all a favor and look at your RPMs when you cross the finish line next time and you can know for sure. If this is the case, you can use even more gear. A 4.10 will cross at 119 in fourth.

btw, an auto with 3.27s will cross in third at 112 mph....probably result in a faster time.

with that said, if you want the most out of the 1/4 with stock type power and have an auto, get 4.10s. if you want up to 500 rwhp, get 3.70s. stock or bolt on power levels aren't going to push 3.70s, they will be more fun on the street though.

don't fear the gear! my race car has 5.83s....contemplating a move to 6.0s....

[inferno camaro]

If you let it shift by itself, and before it shifts the last time hit the downshift paddle and it will show you what gear your in. The car won't downshift it will say shift denied. My car was shifting into 5th right before the end of the quarter [109 mph] and I raised my shift points and even bumped my limiter a little. My car instantly gained 4mph and .35 in the 1/4. You should be good to around 123 in fourth with stock tire diameter and normal converter slip @6500.

[E.T.]

Originally Posted by inferno camaro

If you let it shift by itself, and before it shifts the last time hit the downshift paddle and it will show you what gear your in. The car won't downshift it will say shift denied. My car was shifting into 5th right before the end of the quarter [109 mph] and I raised my shift points and even bumped my limiter a little. My car instantly gained 4mph and .35 in the 1/4. You should be good to around 123 in fourth with stock tire diameter and normal converter slip @6500.

Is there any reason mine would be in fifth? I ran it in sport mode and the shifts are all very close to redline, so I don't see how I could possibly be in fifth. I'd have to run out fourth, but if I did that, I'd be at 130+ mph. Also, I believe Ted bumped up my rev limiter by a few hundred RPMs in my tune.

[Higgs Boson]

do you have a logger or scanner that will display current gear?

converter slip is a real thing so inferno does have a point.....

[infernometallicSS]

Originally Posted by Higgs Boson

you want to cross the finish line at 6500 in fourth.

do you have an auto or stick?

manual trans with 3.91 will go 138 MPH at the top of 4th (6500)....

auto trans with 3.70 will go 132 MPH at the top of 4th (6500)....

of course, that is IF you have the power to push those MPH in the quarter. if you are going 109 in the quarter mile, then you are shifting to fourth right at 99 MPH...and crossing the finish line at 5400 RPMs.

Do us all a favor and look at your RPMs when you cross the finish line next time and you can know for sure. If this is the case, you can use even more gear. A 4.10 will cross at 119 in fourth.

btw, an auto with 3.27s will cross in third at 112 mph....probably result in a faster time.

with that said, if you want the most out of the 1/4 with stock type power and have an auto, get 4.10s. if you want up to 500 rwhp, get 3.70s. stock or bolt on power levels aren't going to push 3.70s, they will be more fun on the street though.

don't fear the gear! my race car has 5.83s....contemplating a move to 6.0s....

I have an L99 and I was trapping 111 and I would shift into 4th right before the line. Even being stock when I was trapping like 107 I was shifting into 4th right before the line. Stock gears.

[inferno camaro]

I would say your shifting into fourth if your trapping around 100. You shouldn't hit 5th until about 123-125 roughly at 6400- 6500. What is your redline set at, mine is at 6800.

Originally Posted by E.T.

Is there any reason mine would be in fifth? I ran it in sport mode and the shifts are all very close to redline, so I don't see how I could possibly be in fifth. I'd have to run out fourth, but if I did that, I'd be at 130+ mph. Also, I believe Ted bumped up my rev limiter by a few hundred RPMs in my tune.

[inferno camaro]

With stock tires and 3.70 gear the chart shows 130.4mph @ 66500 then you take the slip of the converter which is 4-7% on decent converters, mine was 5% so I will use that and it would go 123.9mph in 4th @6500.

[E.T.]

I think my redline is 200 over stock, so 6400 I think? I asked my tuner what my car's shift points are at WOT, so we'll see what he says.

[inferno camaro]

The bad thing with these trans is shift points go off of mph instead of rpm. So he may not be able to answer that with out data logging.

[SSE 4 2SS]

I can't answer since I'm over 180 in fourth....over 140 in third..

Seriously, LS3 I was hitting the rev limiter in third or shifting into 4th at the line... Depending on wheel spin and launch...

Most of the L99 cars I've run were in 4th at the stripe...

[Supercharged SS]

With 3.45's I'm in 4th at 140 at 6550. That's crossing the trap. Another 100' and I'd be in 5th. It took a ton on tweaking to figure out exactly how to keep it in 4th while crossing.

[SSE 4 2SS]

Originally Posted by Supercharged SS

With 3.45's I'm in 4th at 140 at 6550. That's crossing the trap. Another 100' and I'd be in 5th. It took a ton on tweaking to figure out exactly how to keep it in 4th while crossing.

Fortunately, you have a good tweaker...

[Supercharged SS]

Originally Posted by SSE 4 2SS

Fortunately, you have a good tweaker...

And I am patient.